body {
    background: #ccc;
}

.wrap {
    width: 600px;
    height: 200px;
    border: 1px solid #000;
    margin: 0 auto;
    background: #fff;
    padding: 20px;
    position: relative;
}

.wrap>div {
    width: 500px;
    height: 50px;
    margin: 0 auto;
}

.wrap>div>input {
    width: 300px;
    height: 35px;
    margin-left: 20px;
}

#loginBtn {
    position: absolute;
    right: 25px;
    bottom: 20px;
    width: 110px;
    height: 35px;
}